| 摘要 |
An image reconstruction system and method based on image projection data collected by an imaging system having N tubes of response (TORs) having N&phgr; axial translation symmetries and N&thetas; in-plane rotation symmetries between the TORs. A system matrix mapping image projection data to pixels of an image is used, where the pixels are positioned according to a polar or cylindrical coordinate grid. During image reconstruction, matrix-vector computations are performed between the system matrix and vectors containing image estimates or image projection estimates. The matrix-vector computations are accelerated by structuring the system matrix coefficients, image vectors, and projection measurement vectors in such a way that symmetric data is stored in contiguous memory locations. Further, instead of storing the coefficients for all TOR and voxel combinations, matrix coefficients for only the subset of non-symmetric TOR and voxel combinations are stored, and the same coefficients are reused for the other symmetric TOR/voxel combinations.
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